燕麦β-葡聚糖-蛋白复合纳米颗粒的制备及其负载α-硫辛酸

Preparation of oat β-glucan-protein composite nanoparticles and encapsulation of α-lipoic acid

摘要:

采用酪蛋白酸钠和燕麦β-葡聚糖通过美拉德反应形成的聚合物(Maillard Conjugate,MC)来作为稳定玉米醇溶蛋白(Zein)的涂层。通过反溶剂共沉淀制备出以玉米醇溶蛋白包埋α-硫辛酸(alpha-lipoic acid，LA)为内核，以美拉德聚合物为外壳的复合纳米颗粒(LA-Zein-MC nanoparticle)。研究发现，复合纳米颗粒最佳制备工艺条件为玉米醇溶蛋白和α-硫辛酸的质量比为25:1，玉米醇溶蛋白和美拉德聚合物质量比为1:2.4。制备所得的复合纳米颗粒粒径为235.4 nm，zeta电位为-32.1 mV，PDI为0.144。最大包埋率为58.79%。并利用扫描电镜(SEM)、傅里叶红外光谱(FTIR)、X-射线衍射(XRD)、差示扫描量热(DSC)表征方法验证复合纳米颗粒形貌光滑，α-硫辛酸被包埋在复合纳米颗粒内部，α-硫辛酸以无定型形式存在。稳定性测定表明该结构的复合纳米颗粒具有较高的的盐稳定性、pH稳定性和热稳定性。对疏水性活性物质的包埋运载具有重要借鉴意义。

Abstract:

The Maillard conjugate (MC))formed by Maillard reaction of sodium caseinate and oat β-glucan was used as the coating for stabilizing Zein. Composite LA-Zein-MC nanoparticles were prepared by anti-solvent co-precipitation method, with α-lipoic acid (LA) embedded in Zein as the core and Maillard conjugate as the shell. The study found that the optimum preparation conditions of composite nanoparticles were as follows: the mass ratio of Zein to α-lipoic acid was 25:1, and the mass ratio of Zein to Maillard polymer was 1:2.4. The prepared composite nanoparticles have a particle size of 235.4 nm, zeta potential of -32.1 mV and PDI of 0.144. The maximum encapsulation rate was 58.79%. The characterization methods of scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X- ray diffraction (XRD) and differential scanning calorimetry (DSC) showed that the composite nanoparticles had smooth morphology and α -lipoic acid was embedded. Inside the composite nanoparticles, alpha-lipoic acid exists in an amorphous form. Stability measurement shows that the composite nanoparticles with this structure have high salt stability, pH stability and thermal stability. It has important reference significance for embedding and carrying hydrophobic active substances.